Lemon Squash. PICTURE: Goran Kosanovic
Lemon Squash (Makes 4 240ml jars)

Use organic, unwaxed lemons when possible, or scrub conventional lemons, as the rind is integral to the recipe. If you use Meyer lemons, the squash will have a slight floral note. To zest the fruit, you can use a channel knife, a.k.a. a citrus stripper, which has a U-shaped blade to create long, thin strips of citrus zest. If you're going to can the squash you'll need clean jars and rings, and new lids.

10 lemons 
4 cups water
3 cups sugar

Use a vegetable peeler or channel knife to zest 4 of the lemons.
Bring the water to a boil in a large, wide pot over high heat, then add all the lemons, including the zested ones, and the strips of lemon peel. 
Cook for 2 minutes, then transfer the lemons to a bowl to cool. 
Reserve 2 cups of the lemon cooking water and the boiled strips of lemon peel in a separate medium saucepan.
When the lemons are cool enough to handle, cut them in half, then juice them into a large liquid measuring cup, straining and discarding the pulp, seeds and spent lemon halves. 
The yield should be 1 to 1 1/2 cups.
Add the sugar to the lemon cooking water and lemon peels in the saucepan; bring to a boil over high heat; cook for 5 minutes, then remove from the heat. 
Discard the lemon peels, or reserve them for candying. Stir in the fresh lemon juice until well incorporated.
Fill the jars, leaving a 1/4-inch head space. Wipe the jar rims well and place the lids and rings, tightening until just secure. 
Process for 10 minutes in a boiling-water bath, starting timing from the moment the water returns to a boil. 
Remove the jars from the water bath, setting them upright on a folded towel to cool completely. Make sure the seals are tight before storing, for up to 1 year.

The Washington Post